Dr. Karina Alvina / Neurobiology lab @ Texas Tech University

Research interests

In order to successfully navigate and survive the environment most animals must learn to modify their behavior according to past experiences. This process of learning is mediated by the brain, which controls not only how animals sense their surroundings but also how they respond to changes (both positive and negative). To orchestrate the many different functions of the brain, neurons rely on exquisite communication mechanisms via cellular junctions called synapses.

We are interested in understanding how synapses work, not only in physiological conditions but also in adverse or stressful environments. The brain is central in coordinating the response to stress, and at the same time, a very sensitive target when such response is not controlled. In fact, in humans stress is associated with the onset and exacerbation of a number of brain disorders, including anxiety, depression, drug addiction, post-traumatic stress disorder, and schizophrenia.

Current projects in the lab include:

Modulation of hippocampal function in conditions of chronic stress. The hippocampus is one of the brain regions directly involved in learning and memory formation. It is also one of the most sensitive areas to stress. We will study the effects of chronic and acute stress in specific hippocampal sub-fields using a combination of electrophysiology and behavioral analysis.

Neuropeptide Y (NPY) and resilience to stress. Amongst the many pathways involved in stress processing in the brain, NPY has emerged as a promising “resilience molecule” due to its robust anxiolytic, anti-epileptic and pro-neurogenesis properties. Moreover, NPY levels in specific brain regions, such as the hippocampus, are decreased by stressful conditions, yet the role of endogenously released NPY and the impact of stress-induced changes in NPY on hippocampal function are not clear.

Early life stress (ELS) and hippocampus. It is a well-documented fact that adverse conditions during early development can cause dramatic changes in the brain, however the precise mechanism involved are far from clear. We will use a known paradigm for early stress (limited nesting model) to fully characterize changes in hippocampal synaptic function and behavior in adult mice exposed to ELS. We are specially interested in social behavior.

Hippocampal function, stress and IRISIN, a myokine. Irisin is a skeletal muscle-derived protein that exerts important functions in regulating metabolism and thermogenesis. It is also released after physical exercise, which can counteracts the effects of stress. We will use electrophysiology and behavioral analysis to investigate what are the effects of Irisin on brain function and whether Irisin can effectively be used to treat stress-related disorders.

High Salt diet (HSD), immunity and autism spectrum disorder (ASD). There have been several reports associating parental HSD and autoimmunity. On the the other hand, studies have found an increased incidence of ASD in children whose parents suffered from an autoimmune disease. Therefore, using a mouse model of HSD, we will test the hypothesis that autoimmunity in the parental generation can result in behavioral changes associated with ASD-like behavior in the offspring.